CSS Property:
flex-flow:

Note: Internet Explorer 10 and earlier versions and Safari 5 and earlier versions do not support the flex-flow property.

Result:
A
B
C
D
E
F
CSS Code:
#main {
width:150px;
height: 150px;
border:1px solid black;
display: flex;
flex-flow: row nowrap;
}
Click the property values above to see the result
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